Oxygen Poisoning Mechanism of Catalytic Hydrolysis of OCS over Al2O3 at Room Temperature

The oxygen poisoning mechanism of the catalytic hydrolysis of carbonyl sulfide (OCS) over alumina at room temperature was investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy (in situ DRIFTS), XRD, BET, and ion chromatograph (IC). The surface hydroxyl (-OH) species triggered the catalytic hydrolysis of OCS on Al2O3, with the formation of surface hydrogen thiocarbonate (HSCO2−) species as a key intermediate. Surface SO42- was identified with in situ DRIFTS and IC. It was found that the accumulation of sulfate on catalyst led to the poisoning of Al2O3 in the presence of oxygen.